#region (c) 2014 Nguyễn, M. Hải  - All rights reserved
/*
Simplified BSD License (BSD)
Copyright (c) 2014, Nguyễn, M. Hải ( www.Minh-Hai.com ). All rights reserved.

Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:

    * Redistributions of source code must retain the above copyright notice, this 
      list of conditions and the following disclaimer.

    * Redistributions in binary form must reproduce the above copyright notice, 
      this list of conditions and the following disclaimer in the documentation 
      and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND 
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 
IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 
BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
POSSIBILITY OF SUCH DAMAGE.
*/
#endregion
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Windows.Data;

namespace Thn.Presentation.Controls
{
    public class EnumToIntConverter : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            // Note: as pointed out by Martin in the comments on this answer, this line
            // depends on the enum values being sequentially ordered from 0 onward,
            // since combobox indices are done that way. A more general solution would
            // probably look up where in the GetValues array our value variable
            // appears, then return that index.
            return (int)value;
        }

        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            return Enum.Parse(targetType, value.ToString(), true);
        }
    }
    public class EnumToIEnumerableConverter : IValueConverter
    {
        private Dictionary<Type, List<object>> cache = new Dictionary<Type, List<object>>();

        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            var type = value.GetType();
            if (!this.cache.ContainsKey(type))
            {
                var fields = type.GetFields().Where(field => field.IsLiteral);
                var values = new List<object>();
                foreach (var field in fields)
                {
                    DescriptionAttribute[] a = (DescriptionAttribute[])field.GetCustomAttributes(typeof(DescriptionAttribute), false);
                    //if (a != null && a.Length > 0)
                    //{
                    //    values.Add(a[0].Description);
                    //}
                    //else
                    //{
                    //    values.Add(field.GetValue(value));
                    //}

                    string text;
                    if (a != null && a.Length > 0)
                    {
                        //found -> use custom attribute
                        text = a[0].Description;
                    }
                    else
                    {
                        //none found -> use default value
                        text = string.Format("{0}", field.GetValue(value));

                        //replace underscore with space
                        text = text.Replace('_', ' ');
                    }
                    values.Add(text);
                }
                this.cache[type] = values;
            }

            return this.cache[type];
        }

        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            throw new NotImplementedException();
        }
    }
}